MEPS 366:203-208 (2008)  -  DOI: https://doi.org/10.3354/meps07517

ABSTRACT: An age-at-length relationship was generated for the tiny Indo-Pacific coral reef goby Trimma nasa using presumed daily increment counts of sagittal otoliths from 110 specimens captured in Palau in May 2007. From these data, the estimated maximum age was approximately 87 d, and the average length of the pelagic larval duration was 33.9 ± 3.7 d (SD), nearly 39% of the maximum lifespan. Linear and power regression lines fit the data equally well (r² = 0.8458 and 0.8464, respectively). Mixed model analysis of age, length and sex data produced a better fit, with significant effects of age (p < 0.0001), sex (p = 0.0134) and age × sex interaction (p = 0.0059) on standard length. Males were significantly smaller than females and juveniles when corrected for age (p < 0.05). The male age-at-length relationship was also significantly different from those of females (p = 0.0218) and juveniles (p = 0.0066). Daily mortality rate as calculated by Hoenig’s equation was 4.7%. These findings are in keeping with an increasing body of data demonstrating that small reef fish lead short lives with linear growth and high mortality, with important consequences for their contribution to the biomass and, hence, energy production of coral reefs.

KEY WORDS: Life history · Gobiidae · Trimma nasa · Otoliths · Pelagic larval duration · Cryptobenthic fishes